Bailey's Irish Cream Fudge

OH YuMmmMMmmMmmy!  I searched online for a picture of Bailey's and noticed that there are even more varities that I think I must try.  :)
Several years ago some wonderful person shared this recipe online.  The web site is no longer in existence so, I'm unable to give proper credit. 
We have enjoyed every calorie of this wonderful fudge. 

Bailey's Irish Cream FudgeMakes about 5 pounds of fudge

 In a very large bowl combine:

2 (12 oz each) pkgs milk chocolate chips
1 (12 oz) pkg semi sweet chocolate chips
2 (7 oz each) jars marshmallow cream
2 t. vanilla
2/3 c. Bailey's Irish Cream
2 c. chopped nuts--optional

Set aside.
Line a 10x15 inch pan with foil and spread lightly with butter (I usually spray pan with Pam only and don't use foil or butter on this part).

In a sauce pan combine:
4 1/2 c. sugar
1 (12 oz.) can evaporated milk
1/2 lb. butter
Bring to a boil over medium heat.  Cook slowly, stirring constantly for 11 minutes.  Pour milk mixture over the chocolate chip mixture.  Stir slowly by hand to blend.  (Do not use a mixer.)  Pour into prepared pan.  Chill until set.

Note:  I usually don't have semi sweet chocolate chips so I use 3 bags of milk chocolate chips.  Also, I usually only use a little more than 2 cups of sugar.--ya know to make this a healthy choice-bwaaaahaaahaaa!  This does make the fudge a little bit softer but still very edible.